# File lib/needle/interceptor.rb, line 110
    def with( &block )
      if @with
        raise InterceptorConfigurationError,
          "you cannot redefine 'with' behavior"
      end

      if @doing
        raise InterceptorConfigurationError,
          "cannot specify 'with' after specifying 'doing'"
      end

      if block.nil?
        raise InterceptorConfigurationError,
          "you must specify a block to 'with'"
      end

      @with = block
      self
    end